mach/shock diamonds in blender
I had the same issue a while back.

First, this tutorial gave me the general idea on how to achieve a basic exaust

However, since you just need to make an image it should be easier 



I came up with two ways to do it:

1. The fast way


Create a exhaust shaped cilinder (I used a cylinder, scaled down one face and welded it to an half sphere on the other end), a toroid and a small UV sphere.
Join the toroid and the sphere, then add an Array Modifier to them (or just duplicate them many times).
Play with the materials using the Emission Shader in the Volume socket of the Output Node (a Volume BSDF with 0 density and Emission turned on will do the trick as well): the toroids and spheres will have a simple orange color with some noise, the material of the main shape is shown in the next method






2. The long and (probably) better way

This method requires a bit of math knowledge, so be warned


create the main exhaust shape described before without the toroids and spheres
make this material




The fist color ramp (the purple/blu one) is creating the main exhuast material, the second is creating the rings. The main idea behind this material is to create cylinders in the exhaust shape that you will then use to model the entire thing.

It can be fairly complex if you don't like math or if you are not experienced with Blender, but with some tweaking the results will be awesome, and you can make it more versatile as well



As you can see, these are not complete ideas: it's 1 AM in the morning here so I don't have time to finish them now.

You still need to add some horizontal noise and the little balls in the second method, and you need to tweak the materials to make them look good (I just tryied to explain you the methods, I'm not doing it for you)



Don't panic!

Here you can download the .blend file ;P